It is well known in the prior art to use a tensioned member either within a column or adjacent to a beam for the purpose of adding strength to either a column or a beam structural member. Typically the tensioned member is designed to add strength in a particular axis or direction of force or as against a particular moment. As most structures have a predictable force or loading placed upon them, the use of a tensioned member can be quite beneficial in adding strength where it is required and allowing for the use of a smaller and less expensive column or beam to accommodate a specified type of loading. However, the use of a tensioned member in conjunction with a structural component such as a column or beam brings in additional considerations, such as there needs to be a method by which the tensioned member is properly stretched or pre loaded in its position being normally parallel to the lengthwise axis of the column or beam. This requires an access area or space around the endpoint of the column or beam to effectuate a tensile force upon the tension member that is typically accomplished by an the use of hydraulic equipment, or a mechanical stretching means such as with bolting and threads.
Prior art examples would be U.S. Pat. No. 5,079,879 to Rodriguez that discloses a post tensioning anchorage system. Rodriquez utilizes a tension member in the form of a cable that is pulled or pretensioned at the end of the cable and once the proper tension is set the tension member is held in place by the use of a wedge lock arrangement that secures the cable in a pre stressed situation being designed for the situation wherein there is a poured concrete structure that has a free end access for the purpose of prestressing the tension member. Another example would be in U.S. Pat. No. 4,916,874 to McCoy et al. that discloses an apparatus for reinforcing a concrete brick wall wherein the tension in mechanism is positioned on the top edge of the block wall for the purpose of stretching or pre loading the tension member that is within the brick wall. Again, McCoy et al. requires free access to the top edge of the brick wall to properly set the tension required for the tension member within the brick wall. Similarly, U.S. Pat. No. 1,549,428 to Barrick discloses a cantilevered support column structure in the form of a lamp standard utilizes a tension member within the column, however, again requiring an end access to the column for the purpose of prestressing the tension member. Barrick also states in the disclosure that the use of the tie rod tension members is optional for achieving the required strength, thus Barrick does not view the use of the tension member as mandatory in the lamp standard design which would not really be considered a structural component in any case. In another type of application U.S. Pat. No. 4,624,086 to MacKay discloses a cast-in-place sleeve insert for forming an aperture through a poured concrete wall, although the tension member is used for different purpose, which is to secure the end cap plates onto the sleeve ends for the prevention of poured concrete migrating within the sleeve. However, there is still the same requirement of having to have access to an open end of the sleeve to properly stretch the tension member for the purpose of drawing the end cap plates securely against the sleeve for a concrete tight seal and to secure the sleeve against the concrete form wall. Alternatively, there are special use devices in the prior art such as U.S. Pat. No. 5,313,749 to Conner that disclose the use of a tension member on a conventional structural steel I beam or girder, wherein a portion of the beam axial length is prestressed with the tension member such that the tension member can be stretched inside of the beam ends, however, Conner does not apply to the use of the perpendicular mounting attachment of the beam to another structural member as Conner merely pre induces a moment in the beam to counteract the loads placed on the beam when is incorporated into a structure.
What is needed is a column to structure attachment device that utilizes the well recognized benefits of using prestressed tension members in conjunction with columns and beams in a structural context that add strength and rigidity to the column and beam without increasing the size, expense, or weight of the column or beam structural component. The aforementioned prior art typically focuses upon utilizing the benefits of a pre stressed attention member for a segment or portion of the column or beam and do not utilize the benefit of using a pre stressed tension member for not only the column or beam member but also the end cap portion that effectuates the perpendicular attachment interface between the column or beam and an adjoining structural component. The present invention fulfills this need by providing the a column structural support between a base structure and a beam structural member and more particularly to structural support columns that utilize a tensioned member within the column to add rigidity to the column structure that includes the end cap portions. The present invention of a column to structure attachment device refines this concept to completely position the tensioning member within the column to allow for the column to structure attachment device to be installed as a support between the base structure and the beam structural member without the need for a free column end to properly preload the tensioned member thus making installation much simpler.